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T631 TDR High Specification Coaxial Cable Fault Locator Operation Manual 90/00901209-11 Refer to preface and safety instructions before operating

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T631 TDRHigh Specification Coaxial Cable Fault LocatorOperation Manual

90/00901209-11 Refer to preface and safety instructions before operating

CONTENTS

Page

1. Preface & Safety 52. Introduction 73. Front Panel - Controls & Indicators 114. Power Sources 165. Display 196. Operating Modes 207. Operating Instructions 21

7.1 General 217.2 Switch On 217.3 Programming from the Help Menu 227.4 Setting Dielectric (PVF) 237.5 Connecting to cable under test 277.6 Locating a cable fault 277.7 Use of left hand cursor 287.7.1 Eliminating the length of the test lead 297.7.2 Measuring between two features 29

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CONTENTS

Page

7.7.3 Resetting the LH cursor 307.8 Auto Fault Find 307.9 Return Loss Measurements 327.10 Filter 388. Use of the Memory 39

8.1 Storing a trace 398.2 Recalling a trace 398.3 Comparing a live and stored trace 398.4 Difference between a live and stored trace 40

9. RS232 Printing and PC Interface 4110. Help Menu 4311. Error Messages 4412. Specification 4513. Product Safety Data 53Appendix – Bicotest Product Range 57

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1. PREFACE & SAFETY

1.1 HEALTH AND SAFETY AT WORK ACT 1974 SECTION 6.1 (C)This product is tested and supplied in accordance with published specifications and, when usedin normal or prescribed applications and within the parameters specified, it will not causedanger or hazard to health or safety.

All usage of the product must be in accordance with the Operating Manual for this equipmentand any work on the electrical components housed within the machine must be undertaken byqualified personnel.

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1.2 SAFETY PRECAUTIONS

For connection to live cables up to 600 V RMS use the Bicotest T631F Blocking Filter.

Only fit 3 Ah NiMh cells.

Do not charge the batteries when the ambient temperature is below 0°C.

AC adaptor and its carry pouch are not waterproof.

AC adaptor is for indoor use only.

The main unit is safe and conforms to IEC 1010. The AC adaptor conforms to themanufacturers safety standards.

1.3 BATTERIESThe T631 is provided with a set of 3 Ah rechargeable NiMh cells. These are supplied in thedischarged state and must be charged for 24 hours before use. Charge the batteries asdescribed in section 4.Note that full rated capacity may not be achieved for the first three cyclesof use.

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2. INTRODUCTIONThe Model T631 is a pulse reflection (TDR) Cable Test Set, for locating cable faults andevaluating changes in impedance caused by connectors, taps, terminations etc. Pulsestransmitted into a cable are reflected by cable imperfections. The transmitted pulse and thereflected pulse(s) are shown on the display.The time taken by the pulse to travel to the fault andreturn is a measure of the distance to the fault. Distance to fault is displayed on the screen afterthe cursor is positioned to coincide with the start of the fault pulse. The type of fault can bedetermined by analysis of the displayed waveform.

Although designed principally for 50, 75 and 93 Ω coaxial cables it is equally effective on other cabletypes as a fault locator.

Impedance mismatches can be measured in terms of Return Loss (dBRL) with the locationdisplayed in feet, metres or time.

Principle features include a 15 location memory for trace storage with ability to transfer to aprinter or PC, and dual cursors for point to point measurements.

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2.1 SAMPLE TRACES

1. Open circuit/high impedance series faults

Note: Positive (upward) reflection

2. Short circuit/low impedance shunt faults

Note: Negative (downward) reflection

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Transmit Pulse Reflected Pulse

Transmit Pulse Reflected Pulse

The T631 will display:

a) A “live” trace.

b) A stored trace recalled from the memory.

c) A live and stored trace together for comparison.

d) The difference between a live and stored trace.

2.2 POWER SOURCEThe T631 is powered by 8 rechargeable cells in a compartment accessible from the rear of theT631, or from an external DC power source via the DC jack.

When operated from batteries, the T631 will automatically switch off before the batteries arecompletely discharged.

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2.3 MAIN FEATURESFigure 1 shows the front panel of T631.

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3. FRONT PANEL

3.1 CONTROLS

Switches the unit ON. To conserve battery life the unit will switch off 5 minsafter the last key operation. If automatically switched off all measurementparameters will be restored when switched on again.

Switches the unit OFF. This will reset the instrument to the 6 m range, (orequivalent in feet or time), Gain A1, 2 ns pulse and LINE mode.PVF, units andimpedance will remain as they were before switch off.

Rotary control to adjust the contrast of the screen display. It is recommendedthat it is set to the mid position on switch on to obtain a display.

CURSORS – two independent cursorsAdjusts the position of the appropriate cursor. Cursors move left or right asindicated. If held down the cursor initially moves slowly and will then accelerate.The cursor being moved is displayed as a solid line, the passive cursor is abroken line.

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PULSE WIDTHSEnables the various pulse widths available on each range to be selected. Thepulse widths are either automatically selected (AUTO) or set to a specificvalue (MANUAL) via the HELP menu.

HORIZONTAL EXPANSION (ZOOM)Enables the trace about the solid cursor to be expanded by factors of 2, 4 and 8,depending on range selected (see Section 7.7 and Section 12, Specification forfurther details).

OPERATIONSelects the operating mode (see Section 6 for further details).

DIELECTRICUsed to set the appropriate velocity factor for the cable dielectric. The valuewill increment or decrement. If held down the value changes slowly at first andthen quickens. Also act as numbers 6 and 11.

RANGESelects the displayed range. The range will increase or decrease and if helddown will step through the available ranges. Also act as numbers 7 and 12.

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SHIFTAdjusts the vertical position of the live trace. If held down the trace shifts– slowly at first and then quickens. Also act as numbers 8 and 13.

AMPLITUDEAdjusts the vertical amplitude of the trace. If held down the unit will stepthrough the available gain stages. Also act as numbers 9 and 14.

MEMORYEnables a live trace to be stored into any of 15 memory locations.Also acts asnumber 10.

Enables any of 15 stored traces to be recalled. Also acts as number 15.

BACKLIGHTSwitches the display backlight ON and OFF. The backlight will switch offautomatically after 5 minutes. Also acts as number 5.

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INTERFACECalls up a menu from which the displayed trace and data may be transferredto a printer, or memorised waveforms may be transferred to a PC, or reloadedfrom a PC. Also acts as number 4.

AUTO FAULT FINDCauses the unit to search for the next significant reflection, starting from theright hand cursor position (see Section 7.8). Also acts as number 3.

HELP MENUAccesses a “Help” menu for setting machine parameters (see Section 10).Also acts as number 2.

RETURN LOSSEnables the return loss between the transmitted pulse and a selectedreflected pulse to be determined. Also acts as number 1.

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3.2 CONNECTORSInput/Output

BNC socket to connect to the cable under test.

9 way D connector to interface with a printer or PC.

DC jack to supply 12 – 20 V external DC.Note centre is positive.

3.3 CHARGE INDICATORBattery Charging

Charge Indicator illuminates when the internal battery is being charged.

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4. POWER SOURCES

4.1 INTERNAL BATTERY

4.1.1 RECHARGINGThe cells may be recharged by connecting the AC adaptor to the DC power jack and leaving theequipment switched off. The charge indicator will illuminate while the batteries are beingcharged. Full charge is achieved in 14 hours. A fully charged battery will give approximately 8hours operation if the backlight is not used. (see Section 12 ‘Power Source’ for details ofcharging voltages).

Note:When fitting new cells the initial charge period should be 24 hours and 14 hours thereafter.

4.1.2 MAXIMISING BATTERY LIFEDo not recharge until the Battery Low warning is displayed.

Do not charge for more than 24 hours.

Stay within the RECOMMENDED temperature limits shown in the specification (Section 12).

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4.1.3 REPLACEMENTFigure 2 shows the rear view of the unit.

Cells are accessed by removing the backcover which is secured by 2 fasteners.

See specification (Section 12) for cell type.

It is recommended that cells are replaced asa set of 8.

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Figure 2 – Battery Access

4.2 EXTERNAL DCThe unit will run from an external 12 – 20 V DC power source via the DC jack.This may be eitherthe AC adaptor or any other DC supply that meets the specification. Centre is positive.

Note that the batteries are charged when external 15 – 20V DC power is applied and theunit is switched off – DO NOT FIT NON-RECHARGEABLE BATTERIES.

4.3 MEMORY BACK UP BATTERYThe memory back up battery is a lithium manganese cell which is part of the main PCBassembly.

The life expectancy is typically four years and replacement is recommended every two yearsduring a routine service to avoid possible loss of stored traces.

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5. DISPLAY

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Figure 3 – T631 Display

6. OPERATING MODESThe unit has 4 display modes.

1. Line (L) the trace obtained from the cable connected to the BNC socket is displayed.

2. Memory (M) the trace from a selected memory is displayed.

3. Dual (L & M) the trace obtained from the cable connected to the BNC socket and aselected trace recalled from the memory are displayed simultaneously.

4. DIFF (L – M) the trace displayed is the difference between the trace of the cable connectedto the BNC socket and a selected trace from the memory.

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7. OPERATING INSTRUCTIONS

7.1 GENERALFor correct operation the cable under test should be taken out of service with all sources ofsupply removed. If this is not possible and the cable is energised or likely to become energisedthen the blocking filter accessory should be used.

RF signals present on telecommunications cables may corrupt the display.

7.2 SWITCH-ONPower the unit from previously charged internal batteries or from the AC adaptor, or external DCsource.

Press the on button and the display should appear.

Rotate the contrast control if necessary to obtain a well defined trace.

On receipt from the factory the unit will power up in the LIVE cable mode, on the 6 m range, withthe distance read out in metres, a propagation velocity factor (PVF) of 0.667 and impedance 75 Ω.

The left hand cursor, (dotted), will be at the start of the transmitted pulse (0 m). The right handcursor, (solid), will be approximately one third of the way across the display.

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The distance units, impedance and the Propagation Velocity Factor Mode (i.e.PVF, V, or V2

)

can be re-programmed via the HELP menu and once programmed will be set automaticallyon switch on thereafter.

Should the unit switch off automatically, the last established machine settings are restoredwhen the unit is switched on.

7.3 PROGRAMMING FROM THE HELP MENU

7.3.1 DISTANCE UNITS

Press HELP key to obtain the Menu.

Selects UNITS by pressing the key indicated.

Select Feet, Metres or Time by pressing the appropriate key.

7.3.2 DIELECTRIC PARAMETERSPress HELP key to obtain the Menu.

Select DIELECTRIC by pressing the key indicated.

Select PVF, V, or V2

by pressing the appropriate key.

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7.3.3 IMPEDANCE

Press HELP key to obtain the Menu.

Select IMPEDANCE by pressing the key indicated.

Select 50, 75 or 93 Ω by pressing the appropriate key.

7.3.4 PULSE SELECTIONA fixed pulse width may be selected by pressing HELP, PULSE WIDTH and then choosing therequired pulse. This pulse width will then apply to all ranges and the pulse width control will notfunction until auto is restored, or the unit is switched off.

Auto pulse selection allows the instrument to select a pulse appropriate to the selected range.This mode is selected by pressing HELP and then selecting PULSE WIDTH and AUTO.

7.4 SETTING DIELECTRIC (PVF)

7.4.1 FROM CABLE TYPEThe unit can be directly programmed from the list of cable types contained in the HELP Menu.

To access the Menu, press HELP, press the key appropriate to CABLE TYPE. From the list ofoptions select the appropriate category and then the particular cable type. The available cabletypes are shown in the following table.

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On returning to normal operation the display will confirm the selected PVF value.

Note: The PVF values are nominal values and variations may be encountered. The DIEL keysare then used to set the specific value.

The PVF (DIEL) can also be set using the DIEL controls to the value appropriate to the cableunder test.

OPTION MAIN TYPE SUB TYPE DIELECTRIC SETTING M/µs

(PVF) V V/2

1 TELEPHONE POLY PEJELLY FILLEDPAPER (0.83 uF)PAPER (0.72 uF)

0.6670.640.720.88

200192216264

10096

108132

2 POWER PILC 25 kVXLPEMIC

0.540.520.41

162156123

817862

3 CATV QR PARA IIIPARA IT, TRTX, TX10RG6, RG11, RG59

0.880.820.870.890.82

264246261267246

132123131134123

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OPTION MAIN TYPE SUB TYPE DIELECTRIC SETTING M/µs

PVF V V/2

4 IBM TYPE 1TYPE 2TYPE 3TYPE 6TYPE 9

0.780.780.620.780.69

234234186234207

11711793

117104

5 DATA RG58RG58UTHICK ETHERNETTHIN ETHERNETRG11, RG6

0.780.660.780.670.82

234198234201246

11799

117101123

For conversion 1 metre = 3.28 feet.

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If the value of the PVF or the cable type is not known then the PVF can be determined as follows.

7.4.2 DIELECTRIC CONSTANT (PERMITTIVITY) KNOWN

PVF = 1ε

Example: For polyethylene ε = 2.25

PVF = =1225

0 667.

.

7.4.3 SHORT LENGTH OF SAME TYPE OF CABLE

1. Measure physical length of the sample.

2. Obtain a reading for the apparent length of the cable using any PVF value.

3. Adjust the PVF value until the distance reading indicated is the same as the measuredlength.

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7.5 CONNECTING TO CABLE UNDER TESTConnect the cable under test directly to the BNC socket or via the test lead supplied.

Unless the LH cursor is moved to coincide with the end of the test lead, the distance read out willinclude the length of the test lead which must be subtracted from the reading obtained.

7.6 LOCATING A CABLE FAULTSet the DIEL appropriate to the cable type (see Section 7.4). Select a RANGE to cover the fullcable length. Use “AUTO” Pulse Width selection unless a specific pulse width is preferred.

Adjust the AMP controls until the fault reflection is observed.

If the fault reflection is less than halfway across the screen select a shorter range and anarrower pulse width for optimum results.

If there is no fault reflection there are two possibilities.

1. The cable length is longer than its recorded length. In this case increase the range until areflection is seen.

2. The fault is very close to the position at which the instrument is connected. In this casereduce the range until a reflection is seen. In both cases, use may be made of the autofault find facility (see Section 7.8).

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Adjust the Right Hand cursor controls to bring the RH cursor to the point at which the start of thereflected pulse just leaves the horizontal as shown.

The distance to the fault is as indicated on the LCD.

For closer examination, press ZOOM to expand the trace and reposition the cursor moreprecisely.

Remember to subtract the length of the test lead if used.

7.7 USE OF THE LEFT HAND CURSORThe left hand cursor can be moved to:

1. Eliminate the length of the test lead.

2. Measure between any two features on the trace.

3. When moved the LH cursor becomes the live cursor and changes to a solid line, with theRH cursor becoming a broken line.

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7.7.1 ELIMINATING THE LENGTH OF THE TEST LEADConnect the test lead to the unit. Select 3 m or 6 m range.

Adjust the controls so that the reflection from the end of the test lead is obtained.

Using the LH cursor controls move the LH cursor to the start of the reflection.

Connect the test lead to the cable under test and locate the fault as described in Section 7.6.

NB: The distance to fault is now that from the end of the test lead.

7.7.2 MEASURING BETWEEN TWO FEATURESUsing the LH cursor controls set the LH cursor to the start of the feature on the LH side.

Using the RH cursor controls set the RH cursor to the start of the feature on the RH side.

The RH cursor is then live and becomes a solid line with the LH cursor a broken line.

The distance read out is the distance between thetwo cursors as shown.

In the ZOOM mode, if a cursor is not on the screenit cannot be moved. Therefore if a measurement

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between two features is to be made in ZOOM mode, position cursors at the relevant positions,then ZOOM and make any fine adjustments as necessary. The readout is always the distancebetween the cursors, even if one is not on the screen. Since expansion takes place around thelive (solid) cursor, the ZOOM facility can be activated by either the left or right cursor by movingthe relevant cursor and thereby making it solid.

7.7.3 RESETTING THE LH CURSORThe LH cursor may be reset to `0' for normal measurements by switching the unit off and on.

Note that the instrument is calibrated such that cable lengths are measured from the co-axsocket. Due to the internal wiring of the instrument, this may result in the left hand cursor beingset a short distance into the displayed transmit pulse, especially on the short pulses. This iscorrect and ensures accurate cable length measurements.

7.8 FIND FAULT – ENSURE RANGE SETTING IS FULL AND NOT EXPANDED (ZOOM)The “FIND FAULT” function is a means whereby the unit will automatically scan a cable andlocate the nearest significant feature and configure the parameters of the unit to optimallydisplay the feature.

Pressing the key a second or subsequent time locates the next significant feature along thecable.

It is essential that the PVF is set to the value appropriate to the cable type in order that distancemeasurements are accurate (see Section 7.4).

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Having obtained the display the parameters may then be altered if required.

This feature is intended for use on coaxial cables where the reflection from a fault may be quitesmall, so the sensitivity used is quite high. On a power cable or twisted pair telephone cable,mismatches due to joints, or change of cable type may give rise to many reflections which theinstrument will detect even though they are not faults.

7.8.1 OPERATIONThe FIND FAULT function starts at the location of the RH cursor and searches to the right.Therefore for a full search the RH cursor should first be placed just to the right of the transmitpulse.

Pressing the FIND FAULT key will start the search. This may take several seconds. Whilesearching, “AFF” is displayed in place of the usual mode display.

Searching is carried out on all ranges from the one appropriate to the starting cursor position(6 m range if the cursor starts on zero) to 12 Km. Gain and Pulse Widths appropriate to therange are used.

When a fault is found, the unit will beep twice and place the RH cursor just before the fault. If nofault is found the unit will beep 4 times, and return to the original conditions.

Pressing FIND FAULT again will cause the next fault to be found. Note that “FIND FAULT” maychange the machine settings.

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7.9 RETURN LOSS (dBRL) MEASUREMENTSThe T631 has two principles of operation.

1. Simple fault location.

2. Qualitative measurement and location.

In the Simple Fault Location mode the pulse width is automatically selected with each range toone best suited to provide a strong reflection from the fault, in order to easily identify and locateit. No significant conclusion can be drawn from the amplitude of the reflected pulse although itspolarity is indicative of the type of fault.

i.e. Upwards – positive – high series impedance

Downwards – negative – low shunt impedance

In order to gain a measure of the significance of the reflection it is necessary to compare theamplitude of the reflected pulse with that of the transmitted pulse.

The amplitude of the reflection resulting from an impedance change, relative to that of thetransmitted pulse is a measure of the impedance mismatch at that point and the ratio is referredto as the reflection coefficient.

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Reflection coefficient ρ = ArAt

where

Ar = amplitude of reflected pulse

At = amplitude of transmitted pulse

The amplitude of the reflected pulse cannot normally exceed that of the transmitted pulse andtherefore the reflection co-efficient cannot exceed unity. It is usual therefore to express thereflection in percentage terms or millirhos (mρ) where:

1000 mρ = 1 rho = 100 % reflection

Impedance mismatches can also be expressed logarithmically in terms of Return Loss where:

Return Loss = 20 log 10

AtAr

dB

or Return Loss = 20 log 10

dB

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At

Ar

A conversion chart is given below:

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Reflection Coefficient/Return Loss Conversion Chart

The foregoing assumes an ideal “lossless" cable. In practice, measurements obtained includethe effect of pulse attenuation due to cable loss and requires correction in order to obtain truereturn loss.

i.e. True Return Loss = Measured Return Loss – Pulse Attenuation

Since the amplitude of the reflection varies with the pulse width it is essential when determiningReturn Loss to use the SAME PULSE WIDTH for all measurements.

This is facilitated by the HELP Menu. Press HELP and then the appropriate key forPULSE WIDTH. From the list of options select the pulse appropriate to the measurement. Onreturning to the trace the selected pulse width will be confirmed on the display, and the PULSEkey will be inoperative.

The output impedance of the T631 must be set to match the impedance of the cable under test.

7.9.1 MEASUREMENT OF RETURN LOSS (dBRL)Through the HELP Menu select the IMPEDANCE to match the cable under test.

Similarly select the PULSE WIDTH appropriate to the measurement.

To minimise any possible mismatches the cable under test should be connected directly to theunit using matched connectors.

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Select the appropriate RANGE & PVF.

Set the AMP to A1 (0 db) on the LCD.

Ensure that the LH cursor is set to the start of the transmitted pulse or a particular pulse if aninterfeature measurement is required.

Increase the AMP control until the desired reflection is obtained.

Move the RH cursor to coincide with the start of the reflected pulse.

Check the distance reading to confirm the location - note the distance.

Press dBRL and the Return Loss in dB will be calculated and displayed on the LCD togetherwith the corresponding reflection co-efficient.

The result is “Measured Return Loss” which requires correction for Pulse Attenuation.

Press RS232 key to print results. Note: this option is not displayed on screen but is available.Ensure printer lead is plugged into the instrument and printer and that the printer is ready toprint (see section 9).

Press key 8 to return to normal operation.

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Notes

a) Note that a positive dB value (or mrho value <1000) indicates a return loss (i.e. thereflection is smaller than the transmit pulse).Under certain conditions it is possible for thereflection to have a greater voltage amplitude than the transmit pulse. In this case the dBvalue will be shown as negative and the mrho figure will be greater than 1000.

b) If the return loss is outside the range of the instrument then XXX dB and XXX mρ will bedisplayed.

c) The position of the cursor prior to pressing dBRL is important as the signal level at thatpoint is used as the zero reference. Be sure to place the cursor on the flat section of thetrace just before the pulse.

d) When measuring very small reflections switching the filter in can improve the performanceof the return loss function.

7.9.2 MEASUREMENT OF PULSE ATTENUATIONThis should be determined using a sample length of the same type of cable as that under test.

Connect the cable directly to the T631 with the end shorted or open.

Measure the Return Loss and the length. Since the cable ends provides a 100% (0dB)reflection, the loss measured is entirely due to the pulse attenuation.

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Divide the loss obtained by the cable length and obtain the pulse attenuation loss in dB permetre or per foot.

Multiply by the distance reading for the cable length noted in the Return Loss measurement toobtain the appropriate pulse attenuation.

Obtain the TRUE RETURN LOSS from:

True Return Loss = Measured Return Loss – Pulse Attenuation.

Note: Pulse Attenuation (Cable Loss) is frequency dependent and will be higher for narrowpulse widths than wider pulse widths. The pulse width used for measuring pulse attenuationMUST be the same as that used to measure the Return Loss.

A library of Pulse Attenuation (Cable Loss) for different cable types for different pulse widths canbe compiled using the procedure detailed in “Measurement of Pulse Attenuation”.

7.10 FILTERA low pass filter is available from the Help menu. It is used to reduce noise, especially on highgain settings. It should not be used with the 2 ns and 10 ns pulses.

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8. USE OF THE MEMORY

8.1 STORING A TRACEObtain the desired LIVE trace using the method previously described in Section 7.

Press the SAVE key and then select the desired Memory location by pressing the appropriatekey.

The live trace is now stored in the selected memory location, together with the associatedmachine settings.

Any trace present in the memory will be overwritten and lost.

8.2 RECALLING A STORED TRACEPress the RECALL key and then select the desired memory location.

The stored trace will then be displayed on the LCD and memory location confirmed.

The machine parameters are set in accordance with the stored trace, and cannot be altered.

8.3 COMPARING A LIVE AND STORED TRACEPress the MODE key and select L & M. The displayed memory waveform will be the last onethat was accessed by either SAVE or RECALL.

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Recall the appropriate stored trace from memory as described earlier.

The machine parameters are set in accordance with the stored trace.

If not already connected to the cable under test, connect to the cable and observe that both thelive trace and the recalled trace are overlaid.

The SHIFT control may be used to separate the traces for easier identification and comparison.The live trace moves relative to the stored trace.

8.4 DIFFERENCE BETWEEN A LIVE AND STORED TRACEPress the MODE key and then select L – M.

Recall the appropriate stored trace from memory as described earlier.The machine parametersare set in accordance with the stored trace.

If not already connected to the cable under test, connect to the cable and observe the tracewhich is the difference between the live and recalled trace.

To view the LIVE trace and recalled trace separately use the MODE key and then select LIVE (L)OR MEMORY (M) as required.

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8.5 HELP MENUWhen in the MEMORY mode, if the HELP menu is accessed, those keys that affect setparameters are disabled.

9. RS232 – PRINTING AND PC INTERFACEScreen information and Memory contents can be transferred to a printer or PC via the RS232interface.

9.1 PRINTINGA suitable printer is the Seiko DPU 411 – 21B available in 220 V 50 Hz or 120 V 60 Hz versions.Other printers may require a different interface cable and printer set-up and details of the RS232interface is given in the specification Section 12.

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9.2 PRINTER SET-UP SEIKO DPU 411-21BThe DIP switch on the printer must be set as shown below.

Connect the interface cable supplied with the printer between the printer and the RS232 port.

Obtain the required display on the screen, either a live trace, a recalled memory trace, or anL & M or L – M trace.

Depress the RS232 key and select menu option 1 “PRINTER”. The display will then display“PRINTING” as the data is transferred to the printer.

9.3 PC TRANSFERA PC software kit, X600 TRACEability™ is available. This enables a cable database to beestablished. Data from all memories can be transmitted to, and received from, a PC. See themanual supplied with the software for full instructions.

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10. HELP MENU MACHINE SET UP

1. Impedance 4. Dielectric 6. Pulse Width93Ω 1 PVF 1 2 ns 1

75Ω 2 V 2 10 ns 2

50Ω 3 V/2 3 30 ns 3Help Menu 7 Help Menu 7 100 ns 4Operation 8 Operation 8 300 ns 5

1200 ns 62. Filter 5. Cable Type Auto 7

Filter ON/OFF Telephone 1 Operation 8Power 2

3. Units CATV 4 7. Help TextFeet 1 IBM 4 Explanation 1Metres 2 Data 5 2Time 3 Help Menu 7 3Help Menu 7 Operation 8 4Operation 8 6

78

8. Operation

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11. ERROR MESSAGESWhen switched on the T631 performs a self test. If it fails the following message is displayed:

INTERNAL MALFUNCTION ERROR XX

PLEASE REFER TO MANUAL

Please contact your supplier and report the error number..

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12. SPECIFICATIONAll specifications in this section assume a PVF of 0.667.1 metre is equivalent to 3.28 feet or 10 nanoseconds.

RANGES AND RESOLUTION:

MaximumDisplayed

Range Nominal

HorizontalExpansion (Zoom)

Resolution atMax Zoom

3 m x1 13 mm6 m x1 26 mm

12 m x1, x2 26 mm25 m x1, x2, x4 26 mm50 m x1, x2, x4, x8 26 mm

100 m x1, x2, x4, x8 52 mm200 m x1, x2, x4, x8 0.1 m400 m x1, x2, x4, x8 0.2 m800 m x1, x2, x4, x8 0.4 m

1600 m x1, x2, x4, x8 0.8 m3200 m x1, x2, x4, x8 1.6 m6400 m x1, x2, x4, x8 3.2 m

12800 m x1, x2, x4, x8 6.4 m

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Radiodetection Ltd.

Accuracy Typically <0.5%(48 m range and above)

Dielectric PVF 0.300 - 0.999V 90 - 300 m/µsV/2 45 - 150 m/µs

Cursors 2

Pulse Characteristics:

Waveform

Amplitude

Pulse Widths

Source Impedance

Connector

Protection

Mode Selection

Filter

Sine SquaredNominally 2.5 V into selectedimpedance2, 10, 30, 100, 300, 1200 ns halfheight nominal50, 75 or 93 ΩBNC Female250 V RMS, 0-60 HzAuto or Manual16 Mhz Low Pass Filter

VERTICAL DEFLECTION:

SENSITIVITY

Gain Setting Signal forFull Scale Deflection

A1A2A3A4A5A6A7A8A9AaAb

16 V8 V4 V2 V

960 mV480 mV240 mV120 mV60 mV30 mV15 mV

Radiodetection Ltd.

T631 OPERATING MANUAL 46

T631 OPERATING MANUAL 47

Radiodetection Ltd.

AUTO MODE PULSE SELECTION

Nominal Range(@PVF = 0.667)

Default Pulse(ns)

Available Pulses(ns)

3 m6 m

12 m24 m48 m96 m

192 m384 m800 m

1600 m& above

22

101030

100100300300

1200

2, 102, 102, 10, 302, 10, 302, 10, 30, 1002, 10, 30, 1002, 10, 30, 100, 3002, 10, 30, 100, 300, 12002, 10, 30, 100, 300, 12002, 10, 30, 100, 300, 1200

Return Loss Measurement Range: 0 dB to > 30 dB

Display Modes Line (L)Memory (M)Comparison (L & M)Difference (L-M)

Memories 15 - Stores trace displayed in Mode L.

Interface RS232 to printer or PC.Connector 9 pin D Male.Configuration 4800 baud, no parity, 8 bits, 1 stop bit.

PIN FUNCTION DIRECTION

2 Received Data (RXD) Input

3 Transmit Data (TXD) Output

5 Ground

6 Data Set Ready (DSR) Input

7 Request To Send (RTS) Output

Display 240 x 128 pixel LCD240 x 100 pixel waveform area

Radiodetection Ltd.

T631 OPERATING MANUAL 48

Backlight LED with auto switch off (5 mins)

Keyboard Sealed membrane

Power Sources Battery - internal rechargeable NiMh provides 8 hours operation (excluding backlight).Cells - 8 x R14

External DC:Operating 12 to 20 V 0.25 ACharging 15 to 20 V 0.25 AConnector 2.1 x 5.5 x 9.5 mm plug centre positive (reverse polarity protection).

Dimensions 300 x 183 x 75 mm

Weight 2.5 kg (including batteries & carry bag)

Accessories Carry bag - soft weatherproof bag with shoulder strap and accessory pouch.AC Adaptors - 120 V or 230 V 50/60 Hz (see separate specification).Test Lead - 3 metre 75 Ω BNC/BNC + BNC/Crocodile clip + BNC/F AdaptorOperating Manual

Safety IEC 1010-1

T631 OPERATING MANUAL 49

Radiodetection Ltd.

AC Adaptors UK230 V ±10% 50 Hz 90 mAOutput 15 V DC 400 mA

North America120 V ±10% 60 Hz 180 mAOutput 15 V DC 400 mA

Europe230 V ±10% 50 Hz 90 mAOutput 15 V DC 400 mA

Environmental & Safety(Main Unit)

Safety

Maximum permissible voltageon input connector for safeoperation

BS EN 61010-1 : 1993 and IEC 1010-1 : 1990 and Amendment 1 : 1992

30 V RMS

Radiodetection Ltd.

T631 OPERATING MANUAL 50

Temperature Operating temperature:Including batteries: 0°C to +50°CExcluding batteries: -5°C to +50°C

Storage temperature:Including batteries: -20°C to +50°CExcluding batteries: -20°C to +65°C

Recommended temperaturelimits to maximise battery life

Damp Heat, Steady State

Damp Heat, Cyclic

Charging: +10°C to +35°CDischarging: -5°C to +45°CStorage: 0°C to +45°C

BS 2011, part 2.1 Ca : 1977 (IEC 68-2-3 : 1969)40°C, 93% RH, 4 days

BS 2011, part 2.1 Db : 1981 (IEC 68-2-30 : 1980)25°C, 95% RH, 12 hr55°C, 93% RH, 12 hr6 cycles

Low Air Pressure BS 2011 part 2.1 M : 1984 (IEC 68-2-13 : 1983)Non operational: 150 mb 16 hoursOperational: 533 mb 30 minutes

T631 OPERATING MANUAL 51

Radiodetection Ltd.

Random Vibration BS 2011 part 2.1 Fdb : 19735 to 150 Hz, 0.005g2/Hz2 hours in each of 3 planes(in soft carry case)

Shock

Bump

BS EN 60068-2-27 : 1993 part 2, test Ea (IEC 68-2-27 : 1987)50g, 11ms(in soft carry case)

BS EN 60068-2-29 : 1993 part 2, test Eb (IEC 68-2-29 : 1987)40g, 6ms, 1000 bumps in each of 3 axes(in soft carry case)

Free Fall

Water and dust Protection

BS EN 60068-2-32 : 1993 part 2, test Ed (IEC 68-2-32 : 1975)1m(in soft carry case)

BS EN 60529 (IEC 529 : 1989)To IP54

Radiodetection Ltd.

T631 OPERATING MANUAL 52

13. PRODUCT SAFETY DATAThe T631 is a Pulse Echo Test Set that provides visual indication of cable faults. The T631 istested and supplied in accordance with our published specifications, and when used in normalor prescribed applications within the parameters specified for electrical and mechanicalperformance, will not present any danger or hazard to health or safety, provided normalengineering and safety practices are observed.

Doubt relating to any aspect of usage of this instrument must be referred to Radiodetection Limited.

13.1 POWER SUPPLY

a) The instrument is fitted with eight rechargeable NiMh batteries with capacity of 3Ah. The batteries should only be replaced with equivalent cells with the same capacity. Aquick blow fuse that is not accessible to the operator is fitted to protect the battery circuit.

b) The instrument can also be powered with an external 12 to 20 V DC source 0.25 A asoutlined in specification (section 12). A quick blow fuse that is not accessible to theoperator is fitted to offer protection.

c) The instrument can also be powered with an optional AC Adaptor (for further details seespecification, section 12).

T631 OPERATING MANUAL 53

Radiodetection Ltd.

13.2 ROUTINE SERVICINGIt is recommended that the instrument is returned to Radiodetection Limited annually for serviceand calibration checks. The instrument is fitted with eight rechargeable NiMh batterieswith capacity of 3 Ah. Replacement batteries must be of a similar type.

13.3 COMPOSITION/TOXIC HAZARDSUnder normal conditions of use, storage and handling, the T631 presents no toxic hazards,however, in certain circumstances the following could apply:

a) Incineration

The instrument houses NiMh batteries and these must not be incinerated.Additionally someof the electronic components included in the assembly are constructed with resins and otherchemicals which produce toxic fumes during incineration. It is required that the instrument issubmitted to the correct authority for disposal in accordance with local by-laws.

b) Acidic or Caustic Compounds

Some of the electronic components included in the assembly, particularly the electrolyticcapacitors contain acidic compounds. In the event of any damaged items coming into contactwith the skin, the affected area should be washed with clean, cold water. In the event of eyecontamination, thoroughly irrigate with recognised eyewash and seek urgent medicalassistance.

Radiodetection Ltd.

T631 OPERATING MANUAL 54

c) Physical Damage

Some of the components used in the assembly may contain very small quantities of toxicmaterials.There exists a remote possibility that physically damaged components may present atoxic hazard. As a general precaution avoid unnecessary contact with damaged electroniccomponents and arrange for disposal in accordance with local legislation that may currently bein force.

13.4 TRANSPORT AND HANDLINGThe instrument is supplied in a soft carry bag which offers adequate protection under normalworking conditions. For transportation over long distances the instrument should be suitablypacked in a box filled with shock absorbing material such as bubblepack or corrugatedcardboard.

13.5 STORAGEThe instrument should be stored in a dry, clean environment. The NiMh battery will selfdischarge over a period of up to 1 year so it may be necessary to fully charge and dischargethe battery several times, using the recommended adaptor, before full capacity is restored.

No hazard is anticipated during storage.

13.6 DISPOSALWhen disposing of electrical and electronic equipment or packaging materials, exerciseprecautions that are required by local legislation. If in doubt, contact the local authority.

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Radiodetection Ltd.

13.7 SAFE USEThe T631 is designed to be used by suitably trained personnel following the procedures andinstructions described in this operating manual. Additionally, the following points should benoted:

a) Personal Protection/Protective Clothing

Not necessary for operating the T631, providing that normal safe working practice is observed.

b) Working Environment

No special precautions are needed for operating the T631. Appropriate precautions must beobserved for potentially hazardous, working environments such as construction site installations,electricity substations, explosive atmospheres, etc.

Radiodetection Ltd.

T631 OPERATING MANUAL 56

T631 OPERATING MANUAL 57

Radiodetection Ltd.

Other products available from Bicotest:

LEXXI™ T810

A universal hand-held TDR for use on all types of metallic cable, including live AC when used with the blocking filter lead

T600 Series TDRs

World class, user-friendly cable fault locators which feature interface with PCs via X600 TRACEability™ software

T631F, T600FS and T600FD Blocking Filters

Single and dual input LV mains blocking filters for use with T600 series TDRs

T272 High Resistance Cable Fault Locator

For location of high resistance insulation faults of up to 200 megohms

Please contact our sales Office for further information on the above systems.

Global locations Radiodetection (USA) 28 Tower Road, Raymond, Maine 04071, USA Tel: +1 (207) 655 8525 Toll Free: +1 (877) 247 3797 [email protected] www.radiodetection.com

Pearpoint (USA) 39-740 Garand Lane, Unit B, Palm Desert, CA 92211, USA Tel: +1 800 688 8094 Tel: +1 760 343 7350 [email protected] www.pearpoint.com

Radiodetection (Canada) 344 Edgeley Boulevard, Unit 34, Concord, Ontario L4K 4B7, Canada Tel: +1 (905) 660 9995 Toll Free: +1 (800) 665 7953 [email protected] www.radiodetection.com

Radiodetection Ltd. (UK) Western Drive, Bristol, BS14 0AF, UK Tel: +44 (0) 117 976 7776 [email protected] www.radiodetection.com

Radiodetection (France) 13 Grande Rue, 76220, Neuf Marché, France Tel: +33 (0) 2 32 89 93 60 [email protected] http://fr.radiodetection.com

Radiodetection (Benelux) Industriestraat 11, 7041 GD ’s-Heerenberg, Netherlands Tel: +31 (0) 314 66 47 00 [email protected] http://nl.radiodetection.com

Radiodetection (Germany) Groendahlscher Weg 118, 46446 Emmerich am Rhein, Germany Tel: +49 (0) 28 51 92 37 20 [email protected] http://de.radiodetection.com

Radiodetection (Asia-Pacific) Room 708, CC Wu Building, 302-308 Hennessy Road, Wan Chai, Hong Kong SAR, China Tel: +852 2110 8160 [email protected] www.radiodetection.com

Radiodetection (China) Ming Hao Building D304, No. 13 Fuqian Avenue, Tianzhu Town, Shunyi District, Beijing 101312, China Tel: +86 (0) 10 8416-3372 [email protected] http://cn.radiodetection.com

Radiodetection (Australia) Unit H1, 101 Rookwood Road, Yagoona NSW 2199, Australia Tel: +61 (0) 2 9707 3222 [email protected] www.radiodetection.com

Copyright © 2016 Radiodetection Ltd. All rights reserved. Radiodetection is a subsidiary of SPX Corporation. Radiodetection is a trademark of Radiodetection in the United States and/or other countries. Due to a policy of continued development, we reserve the right to alter or amend any published specification without notice. This document may not be copied, reproduced, transmitted, modified or used, in whole or in part, without the prior written consent of Radiodetection Ltd.